Yeah it's pretty powerful  

When I mine with 1 core I get ~740 Kh/s
When I mine with 8 cores, I get 5800 Kh/s (linear increase)
When I mine with 16 cores I get 8900 Kh/s (not linear, supposed to be 11728 Kh/s)
It seems mining with more than 8 cores the miner starts getting less efficient.
Ill stick with two 8-core instances for now.